Outcomes after a first CV event are related to diabetic kidney disease in type 2 diabetes

Background: T2DM has a severe prognosis after a first CV event. We evaluated how survival and risk of further CV events are associated with DKD after a first CV event in T2DM. Materials and methods: In 961 subjects, observed over 14.1 years, death, and incidence of CV events (947 subjects) were censored on December 31st, 2017. DKD phenotypes (DKD-Ph) were defined based on uACR (<30/≥30 mg/g) and CKD-EPI eGFR (≥60/<60 ml/min/1.73 m2). Results: At the census, 229 subjects out of 961 (23.8%) died; 298 out of 947 (31.5%) had a first CV event. Compared to subjects in whom no CV events occurred, the latter were older, more often men, had longer DD, worse CV risk profile, more severe microvascular burden, and a higher rate of CVD prior to recruitment. Over a 6.0-year post-first CV event observation (IQR 2.6-9.7), 99 subjects died (33.2%): 57 (27.4%) in no-DKD and 42 (46.7%) in DKD (p=0.005). The crude HR for all-cause death in DKD (n. 90) vs no-DKD (n. 208) was 1.76 (1.18-2.63, p=0.005), the adjusted HR 1.69 (1.13-2.52, p=0.011). Mortality increased from no-DKD 27.4%, to ACR≥30 alone 38.3%, eGFR<60 alone 50.0%, and ACR≥30/eGFR<60 78.6% (p<0.001), with adjusted HRs of 1.38 (0.84-2.27), 1.66 (0.78-3.52) and 3.32 (1.65-6.64, p=0.001). Over a 3.1 year post-first CV event observation (IQR 0.7-7.1), a new CV event occurred in 124 subjects (41.6%). The events were 82 (39.4%) in no-DKD and 42 (46.7%) in DKD (p=0.019). The unadjusted HR for a new CV event in DKD vs no-DKD was 1.40 (0.96-2.03, p=0.077), with no change after adjustment. Incidence of new CV events: no-DKD 39.4%, ACR≥30 only 45.0%, eGFR<60 only 31.2% and ACR≥30/eGFR<60 71.4% (p<0.001), with adjusted HRs of 1.14 (0.73-1.77, p=0.199), 0.75 (0.30-1.85, p=0.532) and 3.18 (1.57-6.44, p=0.001). Conclusions: High all-cause mortality and high rate of secondary CV events occurred after first-ever vascular event. DKD is associated with higher mortality ad excessive risk of secondary vascular events, mostly the ACR≥30/eGFR<60 DKD phenotype. Funding: PRIN 2020 (2020SH2ZZA).